Installation kit for a pneumatic linear ejector of the type attachable to an arm of a movable arm unwinder

ABSTRACT

An installation kit for a pneumatic linear ejector ( 1 ) comprising an ejector ( 1 ) having a plurality of segments ( 2   a,    2   b,    2   c ) nested one in the other and slidable over each other, the first segment ( 2   a ) and the second segment ( 2   b ) having each a respective central seat ( 3 ) for the passage and/or accommodation of a chuck ( 104 ) configured to grasp a core ( 106 ) of a reel ( 102 ), the seats ( 3 ) being coaxial and defining a central axis (A); the first segment ( 2   a ) being defined by an annular cylinder ( 20 ) attachable to an unwinder ( 100 ) and having a base ( 21 ) adapted to face the unwinder ( 100 ); the annular cylinder ( 20 ) has an outer wall ( 22 ) having an opening ( 15 ), the kit further comprising an adapter ( 37 ) having an annular cavity ( 16 ) adapted to be connected with a fluid source and to be positioned at the opening ( 15 ) for introducing fluid into said annular cylinder ( 20 )

The present invention relates to an installation kit for a linearejector of the type attachable to an arm of a movable arm unwinder. Inparticular, this ejector is of pneumatic type and is used when unloadingreels from self-expanding chucks, mounted to movable arm unwinders. Byway of example, the reels may be made of paper, cardboard, corrugatedcardboard and flexible sheets in general.

The use of self-expanding chucks mounted to one end of each movable armof the aforementioned unwinders is known in the art.

These known self-expanding chucks operate by radial expansion ofexpansion units actuated by an eccentric journal, which is rigidlyjoined to the supporting drive shaft of the movable arm unwinder.

These expansion units automatically protrude out of the self-expandingchucks as the supporting shaft of the unwinder is rotated and allow areel to be retained and centered, and its weight to be supported duringrotation.

It should be noted that, for effective clamping, these chucks exert ahigh radial force, namely on the internal part of the reel, known as“core”, around which the paper or the like is wound. As a result, thecore of the reel remains constrained to at least one self-expandingchuck during the unloading operations, which requires difficult manualactions by the operators for removal thereof. In addition to beinghazardous to the operator, these actions often cause damage to the core.

In an attempt to obviate this drawback, reel unloading devices are knownin the art. One example of such devices is disclosed in patentapplication EP 3153439 A1 by Renova S.r.l. This publication describes atelescopic linear actuator for movable arm unwinders, which comprises afirst annular cylinder having a respective cavity, and a second annularcylinder inserted inside said cavity and able to slide relative to thefirst cylinder. The second annular cylinder also has a respectivecavity. An annular piston is inserted in the cavity of the secondcylinder to be able to slide relative to the second cylinder. Both thecylinders and the annular piston have respective holes for the passageof a self-expanding chuck.

It is well known in the art that the actuator as disclosed in the Renovaapplication is also pneumatically operable. Pneumatic operation isrequired due to the need, as is well known in the art, to apply forcesof about 500 kg to be sure of effectively unloading the reel from thechuck. Lower forces may not be sufficient and leave the core of the reelstuck on the chuck, thereby still requiring an action by the operator.

One drawback of the linear actuator as disclosed in the Renovaapplication is that it requires the chuck to be compatible, specificallyit requires the shaft to be machined in order to supply a pneumaticconnection to the actuator. As a result, the actuator cannot betypically mounted to a machine that doesn't have one, or the pneumaticactuator cannot be combined with a chuck from another manufacturer.

SUMMARY OF THE INVENTION

Therefore, the technical purpose of the present invention is to providean installation kit for a pneumatic linear ejector of the typeattachable to an arm of a movable arm unwinder that can obviate theabove discussed prior art drawbacks.

Namely, one object of the present invention is to provide aninstallation kit for a pneumatic linear ejector of the type attachableto an arm of a movable arm unwinder, that can be adapted to any type ofshaft without machining.

The aforementioned technical purpose and objects are substantiallyfulfilled by an installation kit for a pneumatic linear ejector of thetype attachable to an arm of a movable arm unwinder, that comprises thetechnical features as disclosed in one or more of the accompanyingclaims.

In particular, one embodiment of present invention relates to aninstallation kit for a pneumatic linear ejector of the type attachableto an arm of a movable arm unwinder for reels. This ejector comprises aplurality of segments nested one in the other and slidable relative toeach other. Each segment has a respective seat for the passage and/oraccommodation of a chuck adapted to grasp a core of a reel.

The seats of the segments are coaxial and define a central axis. Thefirst segment is defined by an annular cylinder having a base that canbe attached to an unwinder. The annular cylinder has an outer wallhaving an opening.

The kit further comprises an adapter having an annular cavity adapted tobe connected with a fluid source and to be positioned at the opening forintroducing fluid into the annular cylinder.

The kit solves the technical problem as it allows to adapt any type ofejector or pneumatic actuator to any type of shaft, even lackingpneumatic connections, since this is provided by the external adapter.

Advantageously, it is possible to employ any type of ejector or ofpneumatic adapter with the kit according to the present invention, evenif it initially lacks an opening on the outer wall. Indeed, such openingcan be easily made with tools available in any workshop.

LIST OF FIGURES

Further features and advantages of the present invention will resultmore clearly from the illustrative, non-limiting description of apreferred, non-exclusive embodiment of an installation kit for apneumatic linear ejector of the type attachable to an arm of a movablearm unwinder, as shown in the annexed drawings, in which:

FIG. 1 is an exploded view of a first embodiment of a pneumatic linearejector;

FIG. 2 is a perspective view of a detail of the ejector of FIG. 1;

FIG. 3 is a sectional side view of the ejector of FIGS. 1 and 2;

FIGS. 4a, 4b and 4c are sectional side views of a second embodiment of apneumatic linear ejector part of a kit according to the presentinvention, in a retracted configuration, in an intermediate extendedconfiguration and in a fully extended configuration, respectively;

FIG. 5 is a cross sectional view of an installation kit for a pneumaticlinear ejector according to the present invention;

FIGS. 6a, 6b and 6c are schematic front views of a movable arm unwindercomprising the pneumatic linear ejector of FIG. 1 in respectiveoperating configurations.

DETAILED DESCRIPTION

Referring to the annexed figures, numeral 1 designates a linear ejectorpart of a kit according to the present invention. Specifically, thisejector 1 is of the type attachable to an arm 101 of a movable armunwinder 100 for reels 102. More specifically, the ejector 1 is of thepneumatically operated type.

Particularly referring to FIGS. 6a-6c , the unwinder 100 comprises apair of arms 101, which are vertically arranged. The arms 101 aremovable away from and/or toward each other, in particular driven by amotor 105.

The unwinder 100 comprises a horizontally arranged shaft 103. This shaft103 is connected to an upper end 101 a of one of the arms 101.Preferably, as shown in FIGS. 6a-6c , both arms 101 have respectiveshafts 103. One of the shafts 103 is motorized to unwind the reel 102.

A chuck 104 is coaxially connected to the shaft 103 and is configured tointernally grasp the core 106 of the aforementioned reel 102. Theunwinder 100 preferably comprises a pair of chucks 104. The structureand operation of the chuck 104 are well known to the skilled person andwill not be further described herein.

It should be noted that the chuck 104 as shown in the accompanyingdrawings is of eccentric type, which means that it comprises a cam (notshown) inserted inside a main body 108. Jaws 109 protrude out of themain body 108. As the cam is rotated relative to the main body 108 bythe movement of the shaft 103, it pushes the jaws 109 outwards, therebygrasping the core 106.

Preferably, both shafts 103 have a chuck 104, allowing both ends of thereel 102 to be grasped.

The chuck 104 is connected to the shaft 103 via the ejector 1. Namely,in the case of an eccentric chuck 104 like that depicted in theaccompanying drawings, the ejector 1 is fixed to the shaft 103 androtates therewith. The chuck 104 is directly fixed to the ejector, in amanner that will be further explained hereinbelow. It should be notedthat the unwinder 100 as shown in FIGS. 6a-6c comprises a pair ofejectors 1, each coaxially connected to its respective chuck 104.

Referring to FIG. 1, the ejector 1 comprises a plurality of segments 2a, 2 b, 2 c. These segments 2 a, 2 b, 2 c are nested one in the other.In addition, the segments 2 a, 2 b, 2 c slide relative to each other.

As used herein, the segments 2 a, 2 b, 2 c will be presented in theirpositioning order from the shaft 103 to the reel 102. As a result, thefirst segment 2 a is fixed to the shaft 103, whereas the last segment 2c has an abutment area 7 for contact with a flange 111 of the head.

In the described embodiment, the ejector 1 comprises three segments 2 a,2 b, 2 c, with the last segment 2 c being the third segment from theshaft 103. In alternative embodiments, not shown, the ejector 1 can haveany number of segments 2 a, 2 b, 2 c depending on the type ofapplication and on the force to be applied to the core 106.

Particularly referring to FIGS. 4a-4c , it should be noted that thesegments 2 a, 2 b, 2 c can be alternated between an extendedconfiguration and a retracted configuration under a pneumatic thrust.Namely, FIG. 4a shows a retracted configuration of the ejector 1, FIG.4b shows an intermediate configuration, and FIG. 4c shows an extendedconfiguration.

The first segment 2 a and the second segment 2 b each have a respectiveseat 3 for the passage and/or accommodation of the aforementioned chuck104. These seats 3 are arranged coaxially, thereby defining a centeraxis “A”.

In detail, the first segment 2 a is defined by an annular cylinder 20.Such annular cylinder 20 has a base 21 which, as mentioned above, can bedirectly fixed to the shaft 103.

More in detail, the annular cylinder 20 comprises a base 21 which istransverse, specifically perpendicular, to the center axis “A”. An outerwall 22 and an inner wall 23 extend away from the base 21. The base 21and the walls 22, 23 define a chamber 24 within which the second segment2 b slides.

Referring to FIG. 1, the inner wall 23 of the annular cylinder 20defines the seat 3. A closing portion 25 is fixed to the inner wall 23,and extends transverse, in particular perpendicular to the inner wall23. This closing portion 25 at least partially closes the seat 3 of thefirst segment 2 a. Preferably, the closing portion 25 completely closesthe seat 3, and is configured to support the chuck 104. Therefore, inoperation the chuck 104 is fixed to the closing portion 25. The shaft103 is also fixed to the closing portion 25.

As shown for example in FIGS. 4a-4c , the annular cylinder 20 has anopening 15. This opening 15 is particularly formed on the outer wall 22.Further details about the function of the opening 15 will be provided ina following part of the present disclosure.

Optionally, the first segment 2 a has a further opening 27 on the innerwall 23. It should be noted that the further opening 27 is locatedbetween the closing portion 25 and the base 21 of the annular cylinder20, allowing it to be connected with a corresponding opening (not shown)formed on the shaft 103. Preferably, the first segment 2 a has aplurality of first openings 27, more preferably angularly equidistantfrom the center axis “A”. This affords pneumatic supply to the ejector 1via the shaft 103.

Particularly referring to FIG. 1, it should be noted that the secondsegment 2 b is defined by an annular piston 28 inserted in said annularcylinder 20. The annular piston 28 has an outer cylindrical surface 31,which surrounds an inner cylindrical surface 32. Both cylindricalsurfaces 31, 32 are coaxial with the center axis “A”. A bottom 34 isarranged transverse, in particular perpendicular, to the cylindricalsurfaces 31, 32. The bottom 34 is located inside the chamber 24 of theannular cylinder 20. An outer surface 33 is arranged parallel to thebottom 34 and outside the chamber 24. The annular cylinder 30 has a pairof first seals 26, arranged on the cylindrical surfaces 31, 32, to allowit to slide inside the chamber 24 under the thrust of a fluid,preferably air.

In operation, when pressurized air is introduced into the chamber 24,the annular piston 28 extends away from the base 21 of the annularcylinder 20.

More in detail, it should be noted that the second segment 2 b has aplurality of cylinders 29. Therefore, the last segment 2 c is defined bya plurality of pistons 30, preferably having a cylindrical shape, eachinserted in a respective cylinder 29. In particular, the cylinders 29 ofthe second segment 2 b are in angularly equally spaced arrangementrelative to the center axis “A”. Such cylinders 29 are located betweenthe cylindrical surfaces 31, 32 of the annular piston 28, and inparticular are accessible from the outer surface 33. In the illustratedembodiments, the last segment 2 c of the ejector 1 is defined by eightpistons 30. In alternative embodiments, not shown, any number of pistonsmay be provided.

For pneumatic actuation of the pistons 30 that compose the last segment2 c, the cylinders 29 of the second segment 2 b are in fluidcommunication with the annular cylinder 20 of the first segment 2 a.Each of the cylinders 29 has an open end 35, formed on the bottom 34 ofthe annular piston 28. Each of the pistons 30 has a respective secondseal 36.

It should be noted that the last segment 2 c is configured to abut aflange 111 of the head, namely at a free end 30 a of the pistons 30. Inother words, the aforementioned abutment area 7 is defined by the freeends 30 a of all the pistons 30.

The kit according to the present invention further comprises an adapter37. This adapter 37 has the function of allowing the ejector 1 to bemounted even on shafts 103 that have no pneumatic supply. For thispurpose, the adapter 37 has an annular cavity 17 which, in operation,may be supplied by a source of pressurized fluid, for example air. Theannular cavity 17 is configured to be positioned outside the firstsegment 2 a of the ejector 1, namely at the above discussed opening 15of the annular cylinder 20, to be able to pneumatically supply theannular cylinder 20 from the outside.

More in detail, the adapter 37 has an outer cylindrical wall 39, whichremains stationary in operation. This outer cylindrical wall 39 can beconnected to the pneumatic supply.

More in detail, the adapter 37 comprises a pair of sealing rings 38,which can be associated with the outer wall 22 of the annular cylinder20. These sealing rings 38, with the outer cylindrical wall 39, definethe aforementioned annular cavity 16. In a first embodiment of theinvention, as shown for example in FIGS. 4a-4c , the adapter 37 does notcomprise additional walls between the sealing rings 38 and the outerwall 22 of the annular cylinder 20.

In a second embodiment, as shown for example in FIG. 5, the adapter 37optionally comprises an inner cylindrical wall 41 which can be fixed tothe annular cylinder 20, in particular to the outer wall 22. Here, theinner cylindrical wall of the adapter 37 rotates with the annularcylinder 20 driven by the shaft 103 and has at least one opening 42 thatcan be positioned at the aforementioned opening 15 of the annularcylinder 20. Advantageously, this embodiment may be used with anypneumatic linear actuator or ejector, possibly other than the ejector 1,as long as the above discussed opening 15 has been formed therein.

In order to be mounted to the ejector 1, the adapter 37 comprises abearing 40. In the embodiment of FIG. 4a-4c , the bearing 40 is arrangedbetween the outer cylindrical wall 39 of the adapter 37 and the outerwall 22 of the annular cylinder 20. In the embodiment of FIG. 5, thebearing 40 is arranged between the outer cylindrical wall 39 and theinner cylindrical wall 41 of the adapter 37.

1. Installation kit for a pneumatic linear ejector of the typeattachable to an arm of a movable arm unwinder for reels; said kitcomprising an ejector having a plurality of segments nested one in theother and slidable over each other, the first segment and the secondsegment having each a respective central seat for the passage and/oraccommodation of a chuck configured to grasp a core of a reel, saidseats being coaxial and defining a central axis; the first segment beingdefined by an annular cylinder attachable to an unwinder and having abase adapted to face said unwinder; wherein said annular cylinder has anouter wall having an opening, said kit further comprising an adapterhaving an annular cavity adapted to be connected with a fluid source andto be positioned at the opening for introducing fluid into said annularcylinder.
 2. The kit of claim 1, wherein said adapter comprises a pairof sealing rings which are adapted to be associated with the outer wallof the annular cylinder.
 3. The kit of claim 1, wherein said adapter hasan outer cylindrical wall configured to be placed around the outer wallof the annular cylinder.
 4. The kit of claim 3, also comprising an innercylindrical wall adapted to be fixed to the annular cylinder and has atleast one opening adapted to be placed at the opening of the annularcylinder.
 5. The kit of claim 3, wherein said adapter comprises at leastone bearing adapted to be arranged between the outer cylindrical wall ofthe adapter and the outer wall of the annular cylinder or between theouter cylindrical wall and the inner cylindrical wall of the adapter. 6.The kit of claim 1, wherein said ejector comprises a closing portionfixed to the first segment and closing the seat, said closing portionbeing configured to support said chuck.
 7. The kit of claim 6, whereinsaid first segment has an inner wall defining the seat, said closingportion being connected to said inner wall.
 8. The kit of claim 1,wherein the second segment is defined by an annular piston inserted insaid annular cylinder, the second segment having a plurality ofcylinders, the last segment being defined by a plurality of pistons eachinserted in a respective cylinder of the second segment.
 9. The kit ofclaim 8, wherein the cylinders of the second segment are angularlyequally spaced with respect to said central axis.
 10. An unwinder forreels comprising a pair of vertically arranged arms adapted to move awayfrom and/or toward each other; a horizontally arranged shaft connectedto an upper end of one of said arms; a chuck coaxially connected to saidshaft; a kit according to claim 1, said chuck being fixed to the closingportion of said ejector, said adapter being placed on the outer wall ofthe annular cylinder.